1. Field of the Invention.
The invention relates, in general, to the drilling of wells. More specifically, the invention relates to the spinning together and apart segments of drill pipe such as are used in the drilling of oil and water wells.
2. Related Art.
The drilling of deep holes requires the attachment of many segments of pipe in series. These connections may conventionally be made by threading the male end at the bottom of one pipe into the female end of another. These holes are lengthened as additional pipe lengths are successively added to the drill string in this manner. To remove the drill string, this process is reversed. The present invention offers a device that makes the formation and removal of such strings easier, safer, and quicker.
A number of inventions have attended to the desire for a simple and useful machine for spinning drill pipe. These devices employ a number of different mechanisms for retaining and spinning lengths of pipe.
Rauch, U.S. Pat. No. 6,065,372, offers a power wrench for spinning drill pipe in which the subject pipe length is pressed firmly against two serrated rollers by an idler roller that is actuated by an air ram. The serrated rollers, driven by means of drive chains and a single hydraulic motor, impart spin to the pipe.
Rae, U.S. Pat. No. 5,660,087, discloses a pipe spinner in which a multiplicity of symmetrically located rollers engage and rotate drill pipe sections which are held in place under the force of a piston rod that extends via a bell crank to clamp the pipe.
Brooks, U.S. Pat. No. 4,381,685, provides a power wrench in which a single motor drives a single serrated drum designed to engage and spin the subject pipe segment. The pipe is pressed into firm contact with the serrated surface of the drum using a C-shaped clamp.
Hudson, U.S. Pat. No. 4,221,269, describes a power wrench in which a drill pipe length is received between three urethane-coated rollers that are driven by three rotary hydraulic motors to spin the pipe.
Bartos, U.S. Pat. No. 3,392,609, presents a drill pipe spinning apparatus in which a drill pipe is engaged and rotated by two sets of rollers situated one above the other. Other power wrenches for drill pipe are presented in other patents. However, none of these employ the specific configuration or realize the intrinsic advantages of the present invention.